Methods of forming transistors

ABSTRACT

Some embodiments include methods of forming voids within semiconductor constructions. In some embodiments the voids may be utilized as microstructures for distributing coolant, for guiding electromagnetic radiation, or for separation and/or characterization of materials. Some embodiments include constructions having micro-structures therein which correspond to voids, conduits, insulative structures, semiconductor structures or conductive structures.

TECHNICAL FIELD

Embodiments disclosed herein pertain to methods of forming one or morecovered voids in semiconductor substrates, to methods of forming fieldeffect transistors, to methods of forming semiconductor-on-insulatorsubstrates, to methods of forming spans comprising silicon dioxide, tomethods of forming electromagnetic radiation emitters and conduits, tomethods of forming imager systems, to methods of forming nanofluidicchannels, to fluorimetry methods, to methods of cooling semiconductordevices, and to integrated circuitry.

BACKGROUND OF THE INVENTION

A continuing goal in semiconductor device fabrication is to make thedevices smaller and positioned closer to one another while maintainingthe integrity and desired performance characteristics of the individualdevices. Such has led to the development and improvement of varioussemiconductor constructions, including, for example, recessed accessdevices (RADs), semiconductor-on-insulator constructions, partial and/orpseudo semiconductor-on-insulator constructions, fin field effecttransistors (FinFET) and others. Such may be used in logic, memory, orother circuitry, for example for use in dynamic random access memory(DRAM), NOR, NAND, FLASH memory, and floating body memory, among othersemiconductor devices and circuitry. Semiconductor device fabricationhas also been applied to the development of a diversity ofmicro-structures. For example, such include the development of opticalwave guides fabricated in semiconductor materials and the development ofmicro-electro-mechanical systems (MEMS).

During fabrication, circuitry or micro-structures may be formed to havevoids formed therein. Such may be wholly or partially filled with one ormore materials during subsequent processing, left empty, or evacuated,and any remaining voids may be used for various purposes. Regardless,forming desired voids may be a challenge in achieving desired positionand size of the voids.

A continuing goal of analytical sciences is to develop tools and methodsfor rapid separation and/or characterization of materials. For example,there is a continuing goal to develop tools for rapid separation and/orcharacterization of biomaterials, such as nucleotide sequences and aminoacid sequences. There has been interest in developing micro-structuressuitable for utilization in the separation and/or characterization ofmaterials, but there remains a need for improved methods for making andusing such micro-structures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagrammatic perspective view of a portion of a substrate inprocess in accordance with an embodiment of the invention.

FIG. 2 is a view of the FIG. 1 substrate taken through line 2-2 in FIG.1.

FIG. 3 is a view of the FIG. 1 substrate at a processing step subsequentto that shown by FIG. 1.

FIG. 4 is a view of the FIG. 3 substrate taken through line 4-4 in FIG.3.

FIG. 5 is a view of the FIG. 3 substrate at a processing step subsequentto that shown by FIG. 3.

FIG. 6 is a view of the FIG. 5 substrate taken through line 6-6 in FIG.5.

FIG. 7 is a view of the FIG. 5 substrate at a processing step subsequentto that shown by FIG. 5.

FIG. 8 is a view of the FIG. 7 substrate taken through line 8-8 in FIG.7.

FIG. 9 is a diagrammatic perspective view of a portion of a substrate inprocess in accordance with an embodiment of the invention.

FIG. 10 is a view of the FIG. 9 substrate taken through line 10-10 inFIG. 9.

FIG. 11 is a view of the FIG. 9 substrate at a processing stepsubsequent to that shown by FIG. 9.

FIG. 12 is a view of the FIG. 11 substrate taken through line 12-12 inFIG. 11.

FIG. 13 is a diagrammatic perspective view of a portion of a substratein process in accordance with an embodiment of the invention.

FIG. 14 is a view of the FIG. 13 substrate at a processing stepsubsequent to that shown by FIG. 13.

FIG. 15 is a diagrammatic sectional view of a portion of a substrate inprocess in accordance with an embodiment of the invention.

FIG. 16 is a view of the FIG. 15 substrate at a processing stepsubsequent to that shown by FIG. 15.

FIG. 17 is a view of the FIG. 16 substrate at a processing stepsubsequent to that shown by FIG. 16.

FIG. 18 is a view of the FIG. 17 substrate at a processing stepsubsequent to that shown by FIG. 17.

FIG. 19 is a view of the FIG. 18 substrate at a processing stepsubsequent to that shown by FIG. 18.

FIG. 20 is a diagrammatic sectional view of a portion of a substrate inprocess in accordance with an embodiment of the invention.

FIG. 21 is a view of the FIG. 20 substrate at a processing stepsubsequent to that shown by FIG. 20.

FIG. 22 is a diagrammatic sectional view of a portion of a substrate inprocess in accordance with an embodiment of the invention.

FIG. 23 is a view of the FIG. 22 substrate at a processing stepsubsequent to that shown by FIG. 22.

FIG. 24 is a view of the FIG. 23 substrate at a processing stepsubsequent to that shown by FIG. 23.

FIG. 25 is a view of the FIG. 24 substrate at a processing stepsubsequent to that shown by FIG. 24.

FIG. 26 is a view of the FIG. 25 substrate at a processing stepsubsequent to that shown by FIG. 25.

FIG. 27 is a diagrammatic sectional view of a portion of a substrate inprocess in accordance with an embodiment of the invention.

FIG. 28 is a view of the FIG. 27 substrate at a processing stepsubsequent to that shown by FIG. 27.

FIG. 29 is a diagrammatic sectional view of a portion of a substrate inprocess in accordance with an embodiment of the invention.

FIG. 30 is a view of the FIG. 29 substrate at a processing stepsubsequent to that shown by FIG. 29.

FIG. 31 is a diagrammatic sectional view of a portion of a substrate inprocess in accordance with an embodiment of the invention.

FIG. 32 is a view of the FIG. 31 substrate at a processing stepsubsequent to that shown by FIG. 31.

FIG. 33 is a view of the FIG. 32 substrate at a processing stepsubsequent to that shown by FIG. 32.

FIG. 34 is a view of the FIG. 33 substrate at a processing stepsubsequent to that shown by FIG. 33.

FIG. 35 is a view of the FIG. 34 substrate at a processing stepsubsequent to that shown by FIG. 34.

FIG. 36 is a diagrammatic sectional view of a portion of a substrate inprocess in accordance with an embodiment of the invention.

FIG. 37 is a diagrammatic sectional view of a portion of a substrate inprocess in accordance with an embodiment of the invention.

FIG. 38 is a view of the FIG. 37 substrate at a processing stepsubsequent to that shown by FIG. 37.

FIG. 39 is a diagrammatic sectional view of a portion of a substrate inprocess in accordance with an embodiment of the invention.

FIG. 40 is a view of the FIG. 39 substrate at a processing stepsubsequent to that shown by FIG. 39.

FIG. 41 is a view of the FIG. 40 substrate at a processing stepsubsequent to that shown by FIG. 40.

FIG. 42 is a view of the FIG. 41 substrate at a processing stepsubsequent to that shown by FIG. 41.

FIG. 43 is a view of the FIG. 42 substrate at a processing stepsubsequent to that shown by FIG. 42.

FIG. 44 is a view of the FIG. 43 substrate at a processing stepsubsequent to that shown by FIG. 43.

FIG. 45 is a view of the FIG. 44 substrate at a processing stepsubsequent to that shown by FIG. 44.

FIG. 46 is a diagrammatic perspective view of a portion of a substratein process in accordance with an embodiment of the invention.

FIG. 47 is a view of the FIG. 46 substrate taken through line 47-47 inFIG. 46.

FIG. 48 is a diagrammatic perspective view of a portion of a substratein process in accordance with an embodiment of the invention.

FIG. 49 is a view of the FIG. 48 substrate taken through line 49-49 inFIG. 48.

FIG. 50 is a diagrammatic sectional view of a portion of a substrate inprocess in accordance with an embodiment of the invention.

FIG. 51 is a view of the FIG. 50 substrate at a processing stepsubsequent to that shown by FIG. 50.

FIG. 52 is a view of the FIG. 51 substrate at a processing stepsubsequent to that shown by FIG. 51.

FIG. 53 is a view of the FIG. 52 substrate at a processing stepsubsequent to that shown by FIG. 52.

FIG. 54 is a diagrammatic sectional view of a portion of a substrate inprocess in accordance with an embodiment of the invention.

FIG. 55 is a view of the FIG. 54 substrate at a processing stepsubsequent to that shown by FIG. 54.

FIG. 56 is a view of the FIG. 55 substrate at a processing stepsubsequent to that shown by FIG. 55.

FIG. 57 is a view of the FIG. 56 substrate at a processing stepsubsequent to that shown by FIG. 56.

FIG. 58 is a view of the FIG. 57 substrate at a processing stepsubsequent to that shown by FIG. 57.

FIG. 59 is a diagrammatic sectional view of a portion of a substrate inprocess in accordance with an embodiment of the invention.

FIG. 60 is a view of the FIG. 59 substrate at a processing stepsubsequent to that shown by FIG. 59.

FIG. 61 is a diagrammatic sectional view of a portion of a substrate inprocess in accordance with an embodiment of the invention.

FIG. 62 is a view of the FIG. 61 substrate at a processing stepsubsequent to that shown by FIG. 61.

FIG. 63 is a view of the FIG. 62 substrate at a processing stepsubsequent to that shown by FIG. 62.

FIG. 64 is a diagrammatic sectional view of a portion of a substrate inprocess in accordance with an embodiment of the invention.

FIG. 65 is a view of the FIG. 64 substrate at a processing stepsubsequent to that shown by FIG. 64.

FIG. 66 is a view of the FIG. 65 substrate at a processing stepsubsequent to that shown by FIG. 65.

FIG. 67 is a view of the FIG. 66 substrate at a processing stepsubsequent to that shown by FIG. 66.

FIG. 68 is a view of the FIG. 67 substrate at a processing stepsubsequent to that shown by FIG. 67.

FIG. 69 is a view of the FIG. 68 substrate at a processing stepsubsequent to that shown by FIG. 68.

FIG. 70 is a view of the FIG. 69 substrate at a processing stepsubsequent to that shown by FIG. 69.

FIG. 71 is a diagrammatic sectional view of a portion of a substrate inprocess in accordance with an embodiment of the invention.

FIG. 72 is a view of the FIG. 71 substrate at a processing stepsubsequent to that shown by FIG. 71.

FIG. 73 is a view of the FIG. 72 substrate at a processing stepsubsequent to that shown by FIG. 72.

FIG. 74 is a diagrammatic sectional view of a portion of a substrate inprocess in accordance with an embodiment of the invention.

FIG. 75 is a view of the FIG. 74 substrate at a processing stepsubsequent to that of FIG. 74.

FIG. 76 is a view of the FIG. 75 substrate at a processing stepsubsequent to that of FIG. 75.

FIG. 77 is a view of the FIG. 76 substrate at a processing stepsubsequent to that of FIG. 76.

FIG. 78 is a view of the FIG. 77 substrate at a processing stepsubsequent to that of FIG. 77.

FIG. 79 is a top sectional view of the FIG. 78 substrate along the line79-79; with the FIG. 78 view being along the line 78-78 of FIG. 79.

FIG. 80 is a diagrammatic sectional view of a portion of a substrate inprocess in accordance with an embodiment of the invention.

FIG. 81 is a view of the FIG. 80 substrate at a processing stepsubsequent to that of FIG. 80.

FIG. 82 is a view of the FIG. 81 substrate at a processing stepsubsequent to that of FIG. 81.

FIG. 83 is a view of the FIG. 82 substrate at a processing stepsubsequent to that of FIG. 82.

FIG. 84 is a top sectional view of the FIG. 83 substrate along the line84-84; with the FIG. 83 view being along the line 83-83 of FIG. 84.

FIG. 85 is a diagrammatic sectional view of a portion of a substrate inprocess in accordance with an embodiment of the invention.

FIG. 86 is a view of the FIG. 85 substrate at a processing stepsubsequent to that of FIG. 85.

FIG. 87 is a view of the FIG. 86 substrate at a processing stepsubsequent to that of FIG. 86.

FIG. 88 is a view of the FIG. 87 substrate at a processing stepsubsequent to that of FIG. 87.

FIG. 89 is a view of the FIG. 88 substrate at a processing stepsubsequent to that of FIG. 88.

FIG. 90 is a diagrammatic sectional view of a portion of a substrate inprocess in accordance with an embodiment of the invention.

FIG. 91 is a view of the FIG. 90 substrate at a processing stepsubsequent to that of FIG. 90.

FIG. 92 is a view of the FIG. 91 substrate at a processing stepsubsequent to that of FIG. 91.

FIG. 93 is a diagrammatic perspective view of the FIG. 92 substrate.

FIGS. 94 and 95 are a diagrammatic sectional view and a diagrammatic topview, respectively, of a portion of a substrate in process in accordancewith an embodiment of the invention. The view of FIG. 95 is along theline 95-95 of FIG. 94, and the view of FIG. 94 is along the line 94-94of FIG. 95.

FIGS. 96 and 97 are a diagrammatic sectional view and a diagrammatic topview, respectively, of the substrate of FIGS. 94 and 95 at a processingstage subsequent to that of FIGS. 94 and 95. The view of FIG. 96 isalong the line 96-96 of FIG. 97, and the view of FIG. 97 is along theline 97-97 of FIG. 96.

FIG. 98 is a diagrammatic perspective view of the substrate of FIGS. 96and 97.

FIG. 99 is a diagrammatic view of a computer embodiment.

FIG. 100 is a block diagram showing particular features of themotherboard of the FIG. 99 computer embodiment.

FIG. 101 is a high level block diagram of an electronic systemembodiment.

FIG. 102 is a simplified block diagram of a memory device embodiment.

FIG. 103 is a photomicrograph of a substrate in process in accordancewith one embodiment of the invention.

FIG. 104 is a photomicrograph of the FIG. 103 substrate at a processingstep subsequent to that of FIG. 103.

FIG. 105 is a diagrammatic sectional view of a portion of a substrate inprocess in accordance with an embodiment of the invention, and isalternate processing to that depicted by FIG. 70 subsequent to thatdepicted by FIG. 69.

FIG. 106 is a view of the FIG. 105 substrate at a processing stepsubsequent to that shown by FIG. 106.

DETAILED DESCRIPTION OF EMBODIMENTS

Example embodiments of methods of forming one or more covered voids in asemiconductor substrate are initially described. In the context of thisdocument, the term “semiconductor substrate” or “semiconductivesubstrate” is defined to mean any construction comprising semiconductivematerial, including, but not limited to, bulk semiconductive materialssuch as a semiconductive wafer (either alone or in assemblies comprisingother materials), and semiconductive material layers (either alone or inassemblies comprising other materials). The term “substrate” refers toany supporting structure, including, but not limited to, thesemiconductive substrates described above. The covered void(s) may besubsequently filled in whole or in part with solid, liquid, and/orgaseous material(s). One or more remaining voids may be evacuated of gastherein. Further, a covered void may exist in the final constructionbeing fabricated, a void may be partially filled, or a void may becompletely filled such that no portion of the void exists in the finalconstruction being fabricated. Further and regardless, the one or morecovered voids may be wholly or partially formed within semiconductivematerial of the semiconductor substrate or be received entirely outsideof any semiconductor material of the semiconductor substrate.

Referring initially to FIGS. 1 and 2, a portion of a semiconductorsubstrate is indicated generally with reference numeral 10. In oneembodiment, substrate portion 10 may be considered as comprising a firstmaterial 12, a second material 14, and a third material 16. In oneembodiment, first material 12 comprises a semiconductor material. Forexample and by way of example only, material 12 may comprise, consistessentially of, or consist of one or more of Si, Ge, Ga, Ga/Al, Si/Ge,Ga/As, SiC, and Ga/Al/N, and may be monocrystalline, polycrystalline, oramorphous. For instance, semiconductive material 12 may compriseelemental form silicon, for example monocrystalline silicon such as bulkmonocrystalline silicon of a bulk wafer. In one embodiment, substrate 12comprises a monocrystalline-containing substrate comprising a <100>plane direction as shown (FIG. 1).

Second material 14 is formed over first material 12, and is in whole orin part compositionally different from first material 12. Secondmaterial 14 may be one or more of insulative, conductive, orsemiconductive. Example semiconductive materials include those describedabove for first substrate material 12. Example conductive materialsinclude any conductive metal, alloy of conductive metals, or anysuitable conductive metal compound. Example insulative materials includeat least one of silicon dioxide or silicon nitride. An example thicknessrange for second material 14 is from about 1,500 Angstroms to about3,000 Angstroms.

Third material 16 is received over second material 14, and is in wholeor in part compositionally different from second material 14. An examplethickness range for material 16 is from about 200 Angstroms to about 800Angstroms. Third material 16 may be compositionally the same as ordifferent from first material 12. Regardless, example third materialsinclude elemental-form silicon, including for example elemental-formamorphous silicon and/or monocrystalline silicon, and any one or more ofelemental-form W, elemental-form Ti, a silicide, elemental-form Ge, anda combination of Ga and As. In some embodiments, material 16 may beconsidered as an “epitaxial seed material” which is differentcompositionally from second material 14. In the context of thisdocument, an “epitaxial seed material” is a material which will seedepitaxial growth of a material of the same composition as or differentcomposition from the epitaxial seed material, with some exampleepitaxial growth being described in examples below. The epitaxial seedmaterial may or may not have been epitaxially grown itself. In someembodiments, material 16 may be considered as a “seed material” (notpreceded by “epitaxial”) which is different compositionally from secondmaterial 14. In the context of this document, a “seed material” (notpreceded by “epitaxial”) is a material which will facilitate growth of amaterial of the same composition as or different composition from theseed material. In one embodiment, semiconductor substrate 10 may beconsidered as comprising or defining some mean outermost global surface15 which may or may not be substantially planar.

Referring to FIGS. 3 and 4, a plurality of openings 17, 18, and 19 havebeen formed through third material 16 and second material 14 to firstmaterial 12. In one embodiment, such may be considered as forming orproviding substrate projections 20, 21, 22, and 23. In one embodiment,any two immediately adjacent of such projections may be considered ascomprising a pair of projections comprising second material 14 whichprojects upwardly from or relative to first material 12, and whichcomprises projection sidewalls 24. Openings 17, 18 and 19 may also, ofcourse, be formed to extend into first material 12 (not shown) asopposed to immediately terminating at the outermost surface thereof.

Such provides but one example embodiment of providing exposed differentfirst and second materials on a semiconductor substrate, where thesecond material comprises a pair of projections projecting upwardlyrelative to the first material and comprises sidewalls which in thedepicted example comprise walls of an opening. An exposed third materialis provided atop the second material projections. In one embodiment, aplurality of such openings may be formed by any suitable etching orother technique(s), and whether existing or yet-to-be developed. In theFIGS. 3 and 4 example, openings 17, 18, and 19 are provided to compriseelongated trenches running generally parallel mean outermost globalsurface 15. In one embodiment, trenches 17, 18 and 19 may comprisemonocrystalline-containing material bases 26 which run parallel the<100> plane direction.

Referring to FIGS. 5 and 6, additional first material 13 has beenselectively grown (relative to the second material, at least) fromexposed first material 12 and selectively (relative to the secondmaterial, at least) from exposed third material 16 effective to bridgeacross the respective pairs of second material projections to formcovered voids 28 between the respective pairs of projections. In thecontext of this document, selective growth defines a rate of growthwhich is at least 2:1 compared to all other different compositionexposed material, or at least to some other different compositionexposed material to which the selectively grown material is beingcompared, for at least about 100 Angstroms of growth. By way of exampleonly, the selectively growing may be of conductive material orsemiconductive material. In one embodiment, the selectively growing isdevoid of growing detectable first material 13 from at least a majorityof second material sidewalls 24. In the example FIGS. 5 and 6embodiment, essentially no additional first material 13 grows fromsidewalls 24, with the depicted covering of portions of sidewalls 24 bymaterial 13 within openings 17, 18, and 19 only occurring as the resultof upward growth of material 13 from first material 12 and itself, anddownwardly of material 13 from third material 16 and itself. As material12 and 13 are each of the first material, former bases 26 of material 12within openings 17, 18, and 19 are shown as dashed lines. Such interfaceof material 12 and 13 may or may not be perceptible. In one embodimentthe selectively growing is at a selectively relative to the secondmaterial of at least ten to one, and in one embodiment at least onehundred to one. In one embodiment, the selectively growing of the firstmaterial is of at least 100 Angstroms and achieves selectivity relativeto the second material of at least one hundred to one.

In one embodiment, the selectively growing comprises epitaxialsilicon-comprising growth. For example and by way of example only, amanner of selectively growing epitaxial silicon from examplemonocrystalline silicon material 12 and where third material 16comprises monocrystalline silicon, and/or any one or more ofelemental-form W, elemental-form Ti, or a silicide, includes chemicalvapor deposition using dichlorosilane, hydrogen chloride, and hydrogenat a temperature of 850° C. and at a pressure of 40 Torr. In oneembodiment, the selectively growing comprises growing any one or more ofelemental-form W or a silicide. For example, where third material 16comprises elemental-form silicon, elemental-form W may be selectivelygrown from material 16 by chemical vapor deposition using WF₆ and asilane as precursors at 350 degrees C. and 20 mTorr, and otherwise asdescribed in U.S. Pat. No. 5,043,299. For example, where third material16 comprises elemental-form silicon, titanium silicide may beselectively grown from material 16 by plasma enhanced chemical vapordeposition including simultaneously flowing titanium tetrachloride andhydrogen to the substrate at a temperature of from about 550 degrees C.to about 680 degrees C. at a pressure of about 5 Torr to about 8 Torr(with or without plasma).

In one embodiment, the selectively growing comprisespolysilicon-comprising growth.

In one embodiment where the first material comprises monocrystallineelemental-form silicon comprising a <100> plane direction, thirdmaterial comprises elemental-form monocrystalline silicon comprising a<100> plane direction which is parallel that of the first material.Regardless, in one embodiment where the first material comprisesmonocrystalline elemental-form silicon comprising a <100> planedirection, openings (which may include trenches) are etched to havesides running parallel such <100> plane direction.

In one embodiment, a method of forming a covered void in a semiconductorsubstrate comprises forming a pair of projections projecting upwardlyfrom a semiconductor substrate. By way of example only, any two adjacentof projections 20, 21, 22, and 23 may constitute an example pair of suchprojections. Elemental-form silicon is provided atop the pair ofprojections. For example, material/layer 16 may comprise anyelemental-form silicon. A polysilicon-comprising material is selectivelygrown relative to at least portions of the projection sidewalls from theelemental-form silicon effective to bridge across the pair of openingsto form a covered void between the pair of projections. In oneembodiment, at least some of the selectively grownpolysilicon-comprising material is oxidized to form a silicondioxide-comprising bridge atop the covered void. In one embodiment, allsuch material is oxidized.

In one embodiment, the elemental-form silicon is formed by depositingamorphous silicon and annealing such to be polycrystalline and fromwhich the selectively growing of polysilicon-comprising material occurs.For example, FIG. 103 depicts a photomicrograph of a substrate 900comprising monocrystalline silicon 902, silicon dioxide projections 904,and amorphous silicon 906. Such was formed by deposition of amorphoussilicon, over silicon dioxide, over monocrystalline silicon substrate902. The amorphous silicon and silicon dioxide were etched to formprojections 904 having amorphous silicon 906 thereover, with trenches908 being formed between the projections. Referring to FIG. 104, suchwas annealed at a temperature of about 625° C. which rendered theamorphous silicon polycrystalline. Polysilicon 910 was grown therefromat a temperature of about 850° C. and a pressure of about 40 Torr usingH₂, HCl, and SiH₂Cl₂ as precursors.

In one embodiment, a method of forming a covered void in a semiconductorsubstrate comprises forming a pair of projections projecting upwardlyfrom a semiconductor substrate. By way of example only, any two adjacentof projections 20, 21, 22, and 23 may constitute an example pair of suchprojections. Elemental-form silicon is provided atop the pair ofprojections. For example, material/layer 16 may comprise anyelemental-form silicon. At least one of elemental-form W or a silicideis selectively grown relative to at least portions of the projectionsidewalls from the elemental-form silicon effective to bridge across thepair of projections to form a covered void between the pair ofprojections. By way of example only and with respect to theabove-described embodiment, any of covered voids 28 constitute examplesuch covered voids.

In one embodiment, a method of forming a plurality of covered voids in asemiconductor substrate includes depositing insulative material over anelemental-form silicon-containing material. For example and by way ofexample only, material 12 in the above-described embodiment may comprisean elemental-form silicon-containing material over which an insulativematerial 14 is deposited. Amorphous silicon is deposited over theinsulative material. For example with respect to the above-describedembodiment, material/layer 16 may comprise amorphous silicon which isdeposited over an insulative material 14. An elemental-formsilicon-comprising material is selectively grown relative to theinsulative material from the elemental-form silicon-containing materialand from the amorphous silicon effective to bridge across the pluralityof openings to cover the plurality of openings. For example with respectto the above-described embodiments, material 13 constitutes an exampleelemental-form silicon-comprising material which has been so selectivelygrown.

In one embodiment, a method of forming a plurality of covered voids in asemiconductor substrate comprises depositing insulative material over afirst elemental-form silicon-containing material. A secondelemental-form silicon-containing material is formed over the insulativematerial. A plurality of openings is etched through the secondelemental-form silicon-containing material and the insulative materialto the first elemental-form silicon-containing material. A firstelemental-form silicon-comprising material is epitaxially grown from thefirst elemental-form silicon-containing material. A secondelemental-form silicon-comprising material is selectively grown relativeto the insulative material from the second elemental-formsilicon-containing material effective to bridge across the plurality ofopenings to cover the plurality of openings. Any other of the above andbelow attributes with respect to any other of the disclosed embodimentsare of course contemplated.

In one embodiment, a method of forming a plurality of covered voids in asemiconductor substrate comprises depositing insulative material over afirst elemental-form silicon-containing material. An amorphouselemental-form silicon-containing material is formed over the insulativematerial. A plurality of openings is etched through the amorphouselemental-form silicon-containing material and the insulative materialto the elemental-form silicon-containing material. The amorphouselemental-form silicon-containing material is annealed effective to forma polycrystalline silicon-containing material. A first elemental-formsilicon-comprising material is epitaxially grown from the elemental-formsilicon-containing material while selectively growing relative to theinsulative material a polysilicon-comprising material from thepolycrystalline silicon-containing material effective to bridge acrossthe plurality of openings to cover the plurality of openings. Any otherof the above and below attributes with respect to any other of thedisclosed embodiments are of course contemplated.

Referring to FIGS. 7 and 8, at least a majority of each covered trench28 (not designated in FIGS. 7 and 8) has been filled with one or moreconductive materials 30, whereby for example, the voids exist no more ashaving been completely filled with solid material. Such may be used toform elongated conductive lines therefrom. For example, individual ofthe elongated trenches may be provided to have at least one open endinto or through which conductive material may be deposited to within thecovered elongated trenches effective to form conductive lines within thetrenches. For example, suitable chemical vapor deposition and/or atomiclayer deposition techniques may be utilized to isotropically fillcovered elongated trenches from one or more ends, or from other accesslocation(s) thereto. Such conductive lines may be utilized as localinterconnects, substantially globally running conductive lines, fieldeffect transistor gate lines, and/or other conductive lines.

For example and by way of example only, FIGS. 9-12 depict an alternateembodiment portion of a substrate 10 a. Like numerals from the FIGS. 5-8embodiment substrate have been utilized where appropriate, withdifferences being indicated with the suffix “a” or with differentnumerals. FIGS. 9 and 10 depict the forming of a gate dielectric 32within covered elongated trenches 28 a. An example such material issilicon dioxide, which may be formed for example by a thermal oxidationof material 13 where such comprises at least some elemental-formsilicon. FIGS. 11 and 12 depict conductive material 30 a as having beendeposited to within the covered elongated trenches over gate dielectric32 from at least one open end effective to form conductive gate lineswithin the trenches. Field effect transistor source/drain regions 34 andfield effect transistor channel regions 36 have been formed withinexample selectively grown semiconductive material 13. Such may befabricated by suitable masked or maskless conductivity-modifying dopingof material 13 which extends over projections 20, 21, 22, and 23 andbridges over former voids 28.

In one embodiment, a method of forming field effect transistors includesproviding a monocrystalline silicon-containing substrate which comprisesa <100> plane direction. Insulative material is deposited over themonocrystalline silicon-containing substrate. A plurality of trenchesare etched through the insulative material to silicon-containingmaterial of the substrate parallel the <100> plane direction to providemonocrystalline silicon-containing material bases of the trenches whichrun parallel the <100> plane direction.

An elemental-form silicon-comprising material is epitaxially grown fromthe monocrystalline silicon-containing material of the trench bases andover the insulative material effective to bridge across the trencheswith elemental-form silicon-comprising material and form covered trenchvoids within the trenches. In one embodiment, the monocrystallinesilicon-containing material bases may be wet etched prior to theepitaxially growing. By way of example only, an exposure to a dilute HFsolution comprises an example such wet etching. Regardless and in oneembodiment, an exposed epitaxial seed material different from theinsulative material may be provided over the insulative material priorto the epitaxially growing and from which the elemental-formsilicon-comprising material bridging across the trenches is grown duringthe epitaxially growing. In one embodiment, the epitaxial seed materialand the monocrystalline silicon-containing material bases may be wetetched prior to the epitaxially growing, for example utilizing a diluteHF solution as described above, or using some other solution.

At least one of field effect transistor channel regions or field effecttransistor source/drain regions are formed within the elemental-formsilicon-comprising material which bridges across the trenches. By way ofexample only, FIG. 12 depicts both such field effect transistor regionsand field effect transistor source/drain regions being so formed inmaterial 13 received over material 16. Further in one exampleembodiment, field effect transistor gates are formed within the trenchvoids. In one embodiment, an underside of the elemental-formsilicon-comprising material bridging across the trenches is oxidized toat least partially form a gate dielectric on such underside within thecovered trench voids. After such oxidizing, conductive material isdeposited within the covered trench voids to form field effecttransistor gates within the covered trench voids.

The above-described embodiments depict example secondmaterial-comprising projections which resulted in the formation ofelongated trenches. Any alternative forms of projections, includingcombination of different shaped projections, are also of coursecontemplated. For example, alternate example projections 38 are depictedin FIGS. 13 and 14 with respect to an alternate embodiment substrateportion 10 b. Like numerals from the first-described embodimentsubstrate have been utilized where appropriate, with differences beingindicated with the suffix “b” or with different numerals. FIGS. 13 and14 depict projections 38 as comprising spaced free-standing pillars.FIG. 14 depicts the selectively growing to form material 13 b tocomprise a ceiling which covers a void 28 b, with the ceiling besupported at least in part by the plurality of pillars 38 which arereceived within void 28 b.

The above-depicted embodiments include but example methods of forming acovered void in a semiconductor substrate including the provision ofexposed first, second, and third materials and projections. Alternatemethods and constructions are of course contemplated independent ofprovision of exposed first, second, and third materials. For example andby way of example only, another embodiment substrate portion isindicated generally with reference numeral 40 in FIG. 15. Such includesan example elemental-form silicon-containing material 42 having aconductive material 44 deposited thereover. Example elemental-formsilicon-containing materials include monocrystalline, polycrystalline,or amorphous silicon alone or in combination with other materials.Example conductive materials 44 include any one or combination ofelemental metals, alloys of elemental metals, and/or conductive metalcompounds. An example thickness range for conductive material 44 is fromabout 1,500 Angstroms to about 3,000 Angstroms.

Referring to FIG. 16, a plurality of openings 45, 46, and 47 have beenetched through conductive material 44 to elemental-formsilicon-containing material 42. In one embodiment, openings 45, 46, and47 comprise elongated trenches, for example which run generally parallela mean outermost global surface of the semiconductor substrate, forexample as described in some of the other embodiments. Regardless andfor purposes of the continuing discussion, openings 45, 46, and 47 maybe considered as comprising respective sidewalls 50 and bases 51. Ofcourse, the etching to may also occur into material 42 (not shown) andnot necessarily stop thereon.

Referring to FIG. 17, at least sidewalls 50 of openings 45, 46, and 47have been lined with an insulative material 52. By way of example only,materials include silicon dioxide and/or silicon nitride. An examplethickness range for insulative material 52 is from 60 Angstroms to 300Angstroms. In one embodiment, bases 51 are also lined with insulativematerial 52 while lining sidewalls 50 with insulative material 52. Inone embodiment, material 52 is formed by chemical vapor depositionand/or atomic layer deposition.

Referring to FIG. 18 and in but one embodiment, insulative material 52has been etched from atop the elevational outermost surfaces ofconductive material 44 and from bases 51 within openings 45, 46, and 47.An example technique for doing so includes utilizing a dry anisotropicfluorocarbon etching chemistry.

Referring to FIG. 19, an elemental-form silicon-comprising material 54has been selectively grown relative to the insulative material over aplurality of openings 45, 46, and 47 effective to bridge across suchopenings to cover such openings, thereby forming covered openings orcovered voids 49. In one embodiment, elemental-form silicon-comprisingmaterial 55 has also been epitaxially grown from bases 51 withinopenings 45, 46, and 47 while selectively growing elemental-formsilicon-comprising material 54. By way of examples only, materials 54and 55 may comprise the same or different compositions, and anelemental-form silicon-containing material may be so selectively grownto bridge across the plurality of openings for example as describedabove where conductive material 44 comprises any one or combination ofelemental-form W or a silicide.

In one embodiment, the selectively growing of an elemental-formsilicon-comprising material effective to bridge across the plurality ofopenings may be devoid of epitaxially growing elemental-formsilicon-comprising material from bases of the plurality of openings.FIG. 20 depicts an example alternate embodiment substrate portion 40 acompared to that of FIG. 18. Like numerals from the FIGS. 15-19embodiment have been utilized where appropriate, with differences beingindicated with the suffix “a” or with different numerals. FIG. 20depicts alternate processing of a substrate portion 40 a prior orsubsequent to that of FIG. 17. In FIG. 20, the insulative material 52 ofFIG. 17 has been removed from atop conductive material 44 or neverprovided thereover, but remains as an insulative material lining 52 awithin openings 45, 46, and 47 over bases 51. Such may be accomplishedby any suitable etch or mechanical and/or chemical mechanical polishingprocess of material 52 of FIG. 17 at least to conductive material 44.Alternately by way of example only, some form of selective growth ofmaterial 52 a may be conducted over sidewalls 50 and 51 but not over thetops of material 44. For example and by way of example only, tops ofmaterial 54 may be masked with a suitable layer of material, whilesidewalls 50 and bases 51 are left unmasked during a selective growth ofmaterial 52 a.

Referring to FIG. 21, elemental-form silicon-comprising material 54 hasbeen selectively grown over the plurality of openings 45, 46, and 47 tobridge across and cover such openings, forming covered openings orcovered voids 49 a.

In one embodiment, an exposed seed material or an exposed epitaxial seedmaterial may be provided proximate the tops of the plurality of openingsover the conductive material prior to the selective growth, with suchselective growth being an epitaxial growth from the exposed epitaxialseed material. One alternate example such embodiment is initiallydescribed in connection with a substrate portion 40 b in FIGS. 22-26.Like numerals from the FIGS. 15-19 embodiment have been utilized whereappropriate, with differences being indicated with the suffix “b” orwith different numerals. Referring to FIG. 22, an exposed seed material58 or an exposed epitaxial seed material 58 has been provided overconductive material 44. Example materials include amorphous silicon,monocrystalline silicon, elemental-form W, elemental-form Ti, asilicide, and combinations thereof. An example thickness range formaterial 58 is from about 200 Angstroms to about 800 Angstroms.

Referring to FIG. 23, openings 45 b, 46 b, and 47 b have been etchedthrough material 58 and conductive material 44 to elemental-formsilicon-containing material 42. Accordingly in the depicted embodiment,opening sidewalls 50 b encompass materials 44 and 58. Also for purposesof the continuing discussion, epitaxial seed material as receivedproximate the tops of plurality of openings 45 b, 46 b, and 47 b may beconsidered as comprising elevationally outermost surfaces 60.

Referring to FIG. 24, an insulative material 52 b has been formed toline openings 45 b, 46 b, and 47 b. Referring to FIG. 25, insulativematerial 52 b has been etched effective to remain lining at leastsidewalls 50 b of openings 45 b, 46 b, and 47 b. Referring to FIG. 26,elemental-form silicon-comprising material 54 b has been epitaxiallygrown over the plurality of openings 45 b, 46 b, and 47 b effective tobridge across such openings to cover such openings, thereby formingcovered openings or covered voids 49 b. Elemental-formsilicon-comprising material 55 has also been epitaxially grown frombases 51 of such openings in the depicted embodiment. Further, by way ofexample only in such embodiment, elevationally outermost surfaces 60 ofmaterial 58 were exposed during the selective growth and from whichelemental-form silicon-comprising material 54 was grown during suchepitaxial growth.

An alternate embodiment substrate 40 c is depicted in FIGS. 27 and 28.Like numerals with respect to the 40/40 a/40 b embodiments are utilizedwhere appropriate, with differences being indicated with the suffix “c”or with different numerals. Referring to FIG. 27, insulative material 52c has been formed over sidewalls of material 44 within openings 45 c, 46c, and 47 c as well as over bases 51, but not over the sidewalls ofmaterial 58. For example, material 52 c may be formed utilizing aselective thermal oxidation process whereby a conductive material 44 andelemental-form silicon-containing material 42 are selectively oxidizedrelative to material 58. Such a selective oxidation may be sufficientlyhigh or essentially infinite for the thickness growth of material 52 csuch that none forms on material 58. Alternately, some insulativematerial 52 c may so form. In such instance, a timed etch of material 52c may be conducted to clear oxide from material 58 but not fromconductive material 44 or elemental-form silicon-containing material 42.For example, many suicides (e.g., tungsten silicide, platinum silicide,and cobalt silicide) will oxidize at a considerably slower rate thaneither of elemental-form silicon-containing material 42 or an exampleconductive material 44 of TiN, Ru, or Pt, and a short dilute HF wet etchmay be used to clear any resulting oxide from material 58.

Referring to FIG. 28, elemental-form silicon-comprising material 54 chas been selectively and/or epitaxially grown over the plurality ofopenings 45 c, 46 c, and 47 c effective to bridge across and cover suchopenings, thereby forming covered openings or covered voids 49 c.

FIGS. 29 and 30 depict an alternate embodiment substrate 40 d. Likenumerals have been utilized where appropriate with respect to the 40/40a/40 b/40 c embodiments, with differences being depicted with the suffix“d” or with different numerals. Referring to FIG. 29, insulativematerial 52 d has been formed over the sidewalls of conductive material44 within openings 45 d, 46 d, and 47 d selectively relative tomaterials 58 and 42. Referring to FIG. 30, elemental-formsilicon-comprising material 54 c has been selectively grown over theplurality of openings 45 d, 46 d, and 47 d effective to bridge acrosssuch openings and cover such openings. Epitaxially grown elemental-formsilicon-comprising material 55 has also been grown from opening bases51.

The above-described 40/40 a/40 b/40 c/40 d embodiments provideelevationally outermost surfaces 60 of material 58 to be outwardlyexposed and from which the elemental-form silicon-comprising material 54was grown. An alternate example embodiment substrate 40 e is initiallydescribed with reference to FIGS. 31-35. Like numerals from the above40/40 a/40 b/40 c/40 d embodiments are utilized where appropriate, withdifferences being indicated with the suffix “e” or with differentnumerals. Referring to FIG. 31, and desirably prior to the formationopenings 45 e, 46 e, and 47 e, a masking or covering layer 64 has beenformed over material 58. Some, none or all of such material may remainin the finished construction, and regardless some material compositionother than the composition of material 58 is what is principallycontemplated for material 64 in this particular embodiment. Suchmaterial may be insulative, conductive, and/or semiconductive. By way ofexample only, where material 42 comprises silicon, material 44 comprisesamorphous silicon, and material 58 comprises tungsten silicide, anexample material 64 comprises silicon nitride.

Referring to FIG. 32, at least the sidewalls of the plurality ofopenings 45 e, 46 e, and 47 e through conductive material 44 are linedwith an insulative material 52 e, for example and by way of example onlyanalogous to that depicted and described with respect to insulativematerial 52 c in FIG. 27.

Referring to FIG. 33, elemental-form silicon-comprising material 54 ehas been selectively and/or epitaxially grown over the plurality ofopenings 45 e, 46 e, and 47 e effective to bridge across and cover suchopenings, forming covered openings or covered voids 49 e. Accordingly inthe example FIG. 33 embodiment, elevationally outermost surfaces 60 ofmaterial 58 are covered during such epitaxial growth.

Referring to FIG. 34 and by way of example only, some subsequentprocessing of substrate 40 e has been depicted. Specifically, maskingmaterial 64 is shown as having been removed substantially selectivelyrelative to elemental-form silicon-comprising material 54 e and material58. Further possible subsequent processing is depicted in FIG. 35,whereby material 58 has been selectively removed relative toelemental-form silicon-comprising material 54 e and conductive material44.

FIG. 36 illustrates alternate example subsequent processing with respectto the processing depicted by FIG. 33. Like numerals from the 40 eembodiment have been utilized where appropriate, with differences beingindicated with the suffix “f” or with different numerals. In FIG. 33,elemental-form silicon-comprising material 54 e was not grown to thepoint of bridging over masking material 64. FIG. 36 depicts waferportion 40 f having been processed to grow elemental-formsilicon-comprising material 54 f to bridge over masking material 64.

By way of example only, FIGS. 37 and 38 depict an alternate embodimentsubstrate portion 40 g analogous to that of FIG. 32, but whereininsulative material 52 g is not formed, or has been removed from, overbases 51. Like numerals from the embodiment of FIGS. 32 and 33 have beenutilized where appropriate, with differences being indicated with thesuffix “g”.

Embodiments of methods of forming one or more covered voids in asemiconductor substrate are now additionally described in connectionswith FIGS. 39-45. Referring to FIG. 39, a semiconductor substrateportion is indicated generally with reference numeral 70. Such comprisessome base substrate 72, for example and by way of example only, bulkmonocrystalline silicon. A first material 74 is deposited over substrate72. A second material 76 is deposited over first material 74. A thirdmaterial 78 is deposited over second material 76. Second material 76 isthereby received intermediate first material 74 and third material 78,and second material 76 is compositionally different from first material74 and from third material 78. The first and third materials may becompositionally the same or different. The first and third materials maybe insulative, conductive, and/or semiconductive, with insulative beingpreferred. Example materials include one or a combination of silicondioxide or silicon nitride. By way of example only, example secondmaterials include elemental-form silicon (including amorphous and/orcrystalline forms of elemental-form silicon), elemental-form W,elemental-form Ti, and a silicide, including mixtures/combinationsthereof. For purposes of the continuing discussion, third material 78may be considered as having an elevationally outermost surface 79, andwhich may or may not be planar.

An example thickness range for each of layers 74, 76, and 78 is from 200Angstroms to 3,000 Angstroms. Further by way of example only, firstmaterial 74 may be thicker or thinner than third material 78. Further,third material 78 may be thicker or thinner than second material 76.Further, any two or all three of materials 74, 76, and 78 may be ofabout the same thickness.

Referring to FIG. 40, openings 80 have been formed through thirdmaterial 78, second material 76, and first material 74 to substratematerial 72. Such openings may also, of course, extend into material 72.In one embodiment, openings 80 may be formed by etching, and in oneembodiment comprise a plurality of elongated trenches.

In one embodiment, openings 80 may be considered as providing ordefining respective pairs of upwardly-projecting sidewalls 82 relativeto a semiconductor substrate 70. Sidewalls 82 have a space 83therebetween which comprises opposing first, second, and third materials74, 76, and 78, respectively.

Referring to FIG. 41, a fourth material 86 has been grown from opposingsecond material 76 of sidewalls 82 selectively relative at least tofirst material 74 and third material 78 effective to form a bridge offourth material 86 across space 83 to form respective covered voids 87between sidewalls 82. In one embodiment, essentially no fourth material86 grows from sidewalls of first material 74 and third material 78, withthe depicted covering of portions of sidewalls of materials 74 and 78within openings 80 by material 86 only occurring as the result of upwardand downward growth of material 86 from itself within openings 80. Thesecond and fourth materials may be compositionally the same ordifferent. In one embodiment, such selectively growing forms the fourthmaterial to comprise elemental-form silicon. In one embodiment, thefourth material is formed to comprise any one or more of elemental-formW or a silicide. Example processing and materials may be as described inany of the above-described embodiments. FIG. 41 depicts an embodimentwhereby a material 88 deposits atop and/or also selectively fromsubstrate material 72 during the growth of material 86 from secondmaterial 76. In such event, material 88 may be compositionally the sameas or different from material 86.

FIG. 41 also depicts an embodiment wherein the selectively growing doesnot grow fourth material 86 to extend over an elevationally outermostsurface 79 of third material 78. FIG. 42 depicts continued processingand/or an alternate embodiment whereby the selectively growing ofmaterial 86 is continued sufficiently to grow fourth material 86 toextend over elevationally outermost surfaces 79 of third material 78.

Referring to FIG. 43, substrate 70 has been polished inwardly to atleast third material 78 to leave fourth material 86 bridging overcovered voids 87. FIG. 44 illustrates example subsequent or continuedprocessing whereby polishing of substrate 70 has been conducted inwardlyto at least second material 76 to leave fourth material 86 bridging overcovered voids 87. FIG. 45 illustrates still subsequent or continuedprocessing whereby substrate 70 has been polished inwardly to firstmaterial 74 to still leave some fourth material 86 bridging over coveredvoids 87.

In one embodiment, a method of forming a covered void within asemiconductor substrate includes providing a bulk monocrystallinesilicon-containing substrate. By way of example only with respect toFIG. 39, material 72 may constitute a bulk monocrystallinesilicon-containing substrate. A first insulative material is depositedover the bulk monocrystalline silicon-containing substrate. With respectto the FIG. 39 embodiment, material 74 may comprise an example suchfirst insulative material. An elemental-form silicon-containing materialis deposited over the first insulative material. In the context of theFIG. 39 embodiment, material 76 may comprise an example suchelemental-form silicon-containing material. A second insulative materialis deposited over the elemental-form silicon-containing material. In thecontext of the FIG. 39 embodiment, material 78 may comprise such asecond insulative material. The first insulative material may becompositionally be the same as or different from the second insulativematerial. In one embodiment, the first insulative material comprisessilicon dioxide and the second insulative material comprises siliconnitride. In one embodiment, the elemental-form silicon-containingmaterial deposited over the first insulative material comprisesamorphous silicon and/or monocrystalline silicon.

A plurality of trenches is etched through the second insulativematerial, the elemental-form silicon-containing material, and the firstinsulative material to the bulk silicon-containing material of thesubstrate. By way of example only, FIG. 40 depicts such exampleprocessing. Again of course, etching may occur into material 72.

A silicon-comprising material is selectively grown from theelemental-form silicon-containing material and from the bulksilicon-containing material of the substrate within the trencheseffective to bridge across the trenches with elemental-formsilicon-comprising material to form covered trench voids within thetrenches. By way of example only, FIGS. 41 and 42 depict examples ofsuch processing. In one embodiment, at least one of field effecttransistor channel regions or field effect transistor source/drainregions are formed within the elemental-form silicon-comprising materialbridging across the trenches.

Also of course with respect to any of the above described embodiments,the covered openings/voids which are formed may subsequently be whollyor partially filled with any one or combinations of insulative,conductive, or semiconductive materials. Also and regardless, any of theabove embodiments may not form trenches and/or provide otherconfiguration projections forming one or more covered openings/voids.For example and by way of example only, the embodiment of FIGS. 13 and14 may be utilized in the context of free-standing pillar formation.Regardless, any other of the above and below attributes with respect toany other of the disclosed embodiments are of course contemplated.

Embodiments herein encompass methods of forming a span comprisingsilicon dioxide. For example, an opening comprising sidewalls is formedwithin a semiconductor substrate. Further, the opening may be wholly orpartially formed within semiconductive material of the semiconductorsubstrate or be received entirely outside of any semiconductor materialof the semiconductor substrate. An elemental-form silicon-containingmaterial is selectively grown relative to at least some portion of thesidewalls to bridge across the opening to form a covered cavity withinthe opening. By way of examples only, any of the above-depicted anddescribed embodiments of selectively growing an elemental-formsilicon-containing material to bridge across an opening to form acovered cavity or void within the opening are of course contemplated.

In one embodiment, at least an outermost upper half of the selectivelygrown elemental-form silicon-containing material is oxidized across theopening to form a silicon dioxide-comprising bridge across the openingover the cavity. By way of example only, FIGS. 46 and 47 depict a waferportion 10 c processed in accordance with an example of thejust-described embodiment. FIGS. 46 and 47 depict substrate portion 10of FIGS. 5 and 6 at a processing step alternate to that depicted byFIGS. 7 and 8, and is accordingly designated 10 c. Like numerals fromthe first-described embodiment are utilized where appropriate, withdifferences being indicated with the suffix “c” or with differentnumerals. FIGS. 46 and 47 depict an outermost upper half of selectivelygrown elemental-form silicon-containing material 13 which bridges acrossthe depicted openings as having been oxidized, thereby forming a silicondioxide-comprising bridge 90 across the openings over the cavities andleaving bridging silicon-containing material 13 c. FIGS. 46 and 47depict the oxidizing as being of less than all of the epitaxially grownelemental-form silicon-containing material, with only about half of suchmaterial being oxidized to form the silicon dioxide-comprising bridge90. Regardless and in one embodiment, elemental-form silicon-comprisingmaterial may be epitaxially grown from a base of the opening or openingswhile selectively growing the elemental-form silicon-containing materialwhich bridges across the opening, for example as depicted in FIGS. 46and 47. Elemental-form silicon-containing material 13 may be selectivelygrown from elemental-form silicon-containing material and/or from atleast one of elemental-form W, elemental-form Ti, or a silicide.Processing may otherwise be conducted, by way of example only, asdescribed above in connection with the substrate 10/10 a/10 b and otherembodiments.

FIGS. 48 and 49 illustrate an alternate embodiment substrate portion 10d. Like numerals from the first-described substrate 10/10 c embodimentshave been utilized where appropriate, with differences being indicatedwith the suffix “d” or with different numerals. FIGS. 48 and 49 depictsubstrate portion 10 d wherein all of the selectively grownelemental-form silicon-containing material of FIGS. 5 and 6 has beenoxidized to form a silicon dioxide-comprising bridge 90 d across therespective openings over the respective cavities. Processing mayotherwise occur as described above with respect to the substrate 10/10a/10 b/10 c and other embodiments.

Additional embodiments of methods of forming covered voids in asemiconductor substrate are next described with reference to FIGS.50-53. Referring to FIG. 50, a substrate portion 100 comprises some basesubstrate 102, for example monocrystalline silicon and/or at least oneother semiconductor material. Projections 104, 105, and 106 projectupwardly from substrate 102, and comprise sidewalls 108. Projections104, 105, and 106 comprise different composition first and secondmaterials 110 and 112, respectively, with second material 112 comprisingat least some outwardly-exposed portion which is received over firstmaterial 110. First and second materials 110, 112 may be insulative,conductive, semiconductive, and including any combination thereof.Example materials of construction and dimensions for materials 110 and112 are as described above in connection with the first-describedembodiment for layers 14 and 16, respectively. For purposes of thecontinuing discussion, second material 112 may be considered ascomprising elevationally outermost surfaces 114 and second materialsidewalls 116.

Referring to FIG. 51, a third material 120 has been selectively grownfrom second material 112 elevationally inward along projection sidewalls108 and effective to bridge across projections 104, 105, and 106 withthird material 120 to form respective covered voids 122 between adjacentpairs of the projections. Example attributes, materials, and methods areotherwise as described in connection with any of the above embodiments.The third material may be of the same composition as the secondmaterial, or of different composition. In one embodiment, the thirdmaterial comprises elemental-form silicon, and the selectively growingcomprises selective and/or epitaxial silicon-comprising growth. In oneembodiment, the second material comprises elemental-form silicon. In oneembodiment, the second material comprises any one or more ofelemental-form W, elemental-form Ti, or a silicide. In one embodiment,the second material comprises elemental-form silicon, and theselectively growing comprises any one or more of elemental-form W or asilicide. In one embodiment, the second material comprises any one ormore of elemental-form W, elemental-form Ti, or a silicide, and theselectively growing comprises epitaxial silicon-comprising growth. Inthe FIG. 51 embodiment, selective growth of third material 120 occursfrom exposed elevationally-outermost surfaces 114 of second material 112and from exposed sidewalls surfaces 116 of second material 112.Alternately, portions or all of at least one of such may be coveredduring the selective growth.

Referring to FIG. 52, third material 120 has been removed inwardly atleast to second material 112 and effective to leave a thirdmaterial-comprising bridge 120 across the respective adjacent pair ofprojections over the respective covered voids 122. Such removing maycomprise any one or combination of etching, mechanical polishing, and/orchemical mechanical polishing. Further, such removing of third material120 may be conducted inwardly to first material 110, for example asshown in FIG. 53. Again for example in such instance, such removing ofthe third material is effective to leave a third material-comprisingbridge 120 over the respective pairs of projections over the coveredvoids.

Other attributes and methods may otherwise be as described in any of theabove and below embodiments. For example and by way of example only, thecovered voids may be provided to comprise elongated trenches runninggenerally parallel a mean outermost global surface of the semiconductorsubstrate. Further in one embodiment, at least a majority of suchtrenches may be filled with conductive material to form elongatedconductive lines therefrom. Alternately and by way example only, thepair of projections may be formed to comprise other structures, forexample spaced free-standing pillars, prior to the stated selectivegrowth. In one embodiment, the selective growth may form one or morevoids to be covered by a ceiling supported at least in part by theplurality of pillars received within the void.

Embodiments herein also include methods of cooling semiconductordevices. For example, any of the structures shown and described hereinwhich provide covered trenches or openings may be utilized in suchmethod embodiments and in structure embodiments. Example materials ofconstruction and dimensions are otherwise as disclosed herein. A methodof cooling semiconductor devices in accordance with an embodimentcomprises etching trenches into an insulative material. Anelemental-form silicon-containing material is selectively grown acrossthe trenches to convert the trenches to elongated covered conduits. Atleast one integrated circuit device is formed and is received at leastpartially within the elemental-form silicon-containing material receivedat least across one of the elongated covered conduits. Coolant isprovided within the conduits, and preferably comprises the flowing-ofcoolant therethrough for example in the form of one or both of liquid orgas.

In one embodiment, the trenches are provided to have exposed trenchbases which comprise elemental-form silicon-containing material overwhich the insulative material is deposited. In one embodiment, anelemental-form silicon-containing material was epitaxially grown fromthe trench bases during the selectively growing of the elemental-formsilicon-containing material across the trenches to convert the trenchesto elongated covered conduits.

In one embodiment, etching of the trenches first comprises depositinginsulative material over an elemental-form silicon-containing material.The trenches are then etched into such insulative material. An exposedseed material, which is different from the insulative material, isprovided over the insulative material prior to the selective growth andfrom which the elemental-form silicon-comprising material receivedacross the trenches is selectively grown during such selective growth.Of course, any of the above-described seed materials may be utilized,and regardless such seed material may be provided over the insulativematerial prior to or after the etching to form the trenches. If providedbefore, the act of etching the plurality of trenches will also occurfirst through the seed material and then through the insulativematerial. In one embodiment, the selective growth comprises epitaxialgrowth of the elemental-form silicon-containing material.

Embodiments herein also include methods of formingsemiconductor-on-insulator substrates. For example referring to FIG. 54,a portion of a semiconductor-on-insulator substrate is indicatedgenerally with reference numeral 130. Such comprises some base substrate132, an insulator layer 134 received thereover, and a silicon-containingsemiconductor layer 136 received over insulator layer 134. Basesubstrate 132 may comprises a bulk monocrystalline silicon-containingsubstrate. Example materials for insulator 134 include one or both ofsilicon dioxide or silicon nitride. An example thickness range for layer134 is from about 1,000 Angstroms to about 3,000 Angstroms. An examplethickness range for silicon-containing semiconductor layer 136 is fromabout 600 Angstroms to about 2,000 Angstroms, with example materialsincluding monocrystalline silicon and SiGe_(x), where “x” ranges from0.01 to 2.0.

Referring to FIG. 55, a plurality of openings 138, 140, and 142 havebeen etched through semiconductor layer 136. Such etching may also beconducted to extend openings 138, 140, and 142 partially into orcompletely through insulator layer 134 (not shown in FIG. 55). Openings138, 140, and 142 may be of any shape, for example shapes as disclosedherein, with one embodiment being of elongated trenches runninggenerally parallel a mean outermost global surface of thesemiconductor-on-insulator substrate. Substrate portion 130 in FIG. 55is depicted as having a planar outermost global surface defined by theoutermost surface of silicon-containing semiconductor layer 136,although planarity is of course not required.

Referring to FIG. 56, an elemental-form silicon-comprising material 144has been epitaxially grown over silicon-containing semiconductor layer136 received over insulator layer 134 effective to bridge acrossopenings 138, 140, and 142 with elemental-form silicon-comprisingmaterial, and to form covered voids 146 within openings 138, 140, and142. At least one of field effect transistor channel regions or fieldeffect transistor source/drain regions are formed within theelemental-form silicon-comprising material bridging across openings 138,140, and 142.

For example and by way of example only, FIG. 57 depicts both fieldeffect transistor channel regions 154 and field effect transistorsource/drain regions 156 formed within material 144. Gate constructions148 have been formed directly over openings 138, 140, and 142. Such aredepicted as comprising conductive regions 150 formed over a gatedielectric region 152.

Covered voids 146, in whole or in part, may remain as part of thefinished circuitry construction, for example provided with coolant fluidflowing or statically received therein. In one embodiment, covered voids146 are wholly or partially filled with one, two, or three of any ofconductive, semiconductive, and/or insulative materials. In oneembodiment, a field effect transistor gate construction is providedwithin previous voids 146, and perhaps with gate constructions 148 insuch embodiment being eliminated. Alternately by way of example only,field effect transistor gate constructions may be provided both withinpreviously covered voids 146 and thereover, for example as depicted inFIG. 58. Substrate portion 130 in FIG. 58 is depicted as comprising agate dielectric 160 and conductive material 162 within previous coveredvoids 146. Thereby, example channel regions 154 are gated from above andbelow. By way of example only, the gate dielectric may be formed by athermal oxidation utilizing gases which access covered voids 146 (FIG.57) from one or more ends thereof, followed by an isotropic depositionof any suitable conductive material 162, for example as describedelsewhere in this document.

In one embodiment, FIGS. 54-58 depict epitaxial growth of anelemental-form silicon-comprising material 144 from exposed portions ofan example silicon-containing semiconductor layer 136. By way of exampleonly in but one alternative, an exposed epitaxial seed material may beprovided over the silicon-containing semiconductor layer prior to theepitaxial growth and from which the elemental-form silicon-comprisingmaterial is grown during such epitaxial growth. Such an exampleembodiment is depicted with respect to a substrate portion 130 a inFIGS. 59 and 60. Like numerals from the first-described embodiment havebeen utilized where appropriate, with differences being indicated withthe suffix “a” or with different numerals. FIG. 59 depicts substrateportion 130 a as comprising an exposed epitaxial seed material 166received over silicon-containing semiconductor layer 136, and throughwhich openings 138 a, 140 a, and 142 a are formed. Example epitaxialseed materials are as described elsewhere in this document. FIG. 60depicts subsequent epitaxial growth of an elemental-formsilicon-comprising material 144 a over layer 136 effective to bridgeacross the openings with elemental-form silicon-comprising material 144a to form covered voids 146 within openings 138 a, 140 a, and 142 a.

Another embodiment is described in connection with FIGS. 61-63 withrespect to a substrate portion 130 b. Like numerals from the substrateportion 130 embodiment are utilized where appropriate, with differencesbeing indicated with the suffix “b” or with different numerals.Referring to FIG. 61, openings 138 b, 140 b, and 142 b have not onlybeen etched through semiconductor 136, but also through insulator layer134 to a bulk monocrystalline silicon-containing material 132 of a bulkmonocrystalline silicon-containing substrate. Openings 138 b, 140 b, and142 b comprise monocrystalline silicon-containing bases 168. Of course,etching may also occur into material 132 (not shown).

Referring to FIG. 62, an elemental-form silicon-comprising material 145is epitaxially grown from monocrystalline silicon-containing bases 168,and an elemental-form silicon-comprising material 144 b is epitaxiallygrown from over silicon-containing semiconductor layer 136 received overinsulator layer 134 effective to bridge across openings 138 b, 140 b,and 142 b, and form covered voids 146 b within such openings. At leastone of field effect transistor channel regions or field effecttransistor source/drain regions are formed within elemental-formsilicon-comprising material 144 b bridging across openings 138 b, 140 band 142 b.

Any of the processing and constructions as depicted and described in theFIGS. 54-60 embodiments may be fabricated with respect to the FIG. 62embodiment. For example and by way of example only, FIG. 63 depicts thefabrication of gate constructions 172 within what werepreviously-covered voids 146 b (FIG. 62). Dielectric material 174 hasbeen formed, for example by thermal oxidation of materials 144 b and 145within the covered voids 146 b of FIG. 62. A conductive gate material176 has been subsequently deposited thereover, with at least theuppermost dielectric material 174 received against material 144 bcomprising a gate dielectric. Channel regions 154 b and source/drainregions 156 b have been formed within epitaxially grown elemental-formsilicon-comprising material 144 b.

Embodiments herein encompass integrated circuitry. In one embodiment,integrated circuitry comprises a semiconductor-on-insulator substratehaving some mean outermost global surface. The substrate comprisesmonocrystalline silicon-containing material, an insulator received overthe monocrystalline silicon-containing material, and an elemental-formsilicon-comprising material received over the insulator. A plurality ofelongated cooling conduits runs generally parallel to the mean outermostglobal surface within the insulator (i.e., within at least some portionof the insulator). Cooling fluid is received within the coolingconduits. In certain embodiments, one or both of field effect transistorchannel regions and/or field effect transistor source/drain regions arereceived within the elemental-form silicon-comprising material that isover the cooling conduits. Example constructions, materials, dimensions,and methods of fabrication are otherwise as described anywhere else inthis document.

Embodiments of methods of forming a semiconductor-on-insulator substrateare next described with reference to FIGS. 64-70 with respect to asubstrate portion 200. Referring to FIG. 64, such comprises a basesubstrate 202 having an insulative layer 204 formed thereover. In oneembodiment, an epitaxial seed material 206 or a seed material 206 isformed over insulative material 204. In one embodiment, base substrate202 comprises a bulk monocrystalline silicon wafer and/or a carriersubstrate. Regardless and for purposes of the continuing discussion,base substrate 202 may be considered as comprising a base region 208, asilicon-containing semiconductor region 212 over base region 208, and arelease region 210 provided intermediate silicon-containingsemiconductor region 212 and base region 208. In one embodiment, basesubstrate 202 comprises bulk monocrystalline silicon, and in oneembodiment release region 210 is formed by implanting hydrogen into basesubstrate 202. For example, a hydrogen-implanted release region 210 maybe formed by implanting hydrogen ions (H+) at about 40-210 KeV at a doseof about 5E16/cm². Alternately and by way of example only, anotherexample release region 210 may be formed to comprise an insulator layerreceived over base region 208. For example, such may be formed by thesuitable implant of oxygen atoms and a subsequent anneal to form asilicon dioxide region 210. As an alternate example, a suitable silicondioxide or other layer may be deposited atop a base substrate 208, and asilicon-containing semiconductor region 212 formed thereoversubsequently. Regardless, an example thickness range for release region210 is from about 200 Angstroms to 2 about microns, and some interface215 is inherently provided or formed relative to release region 210 andsilicon-containing semiconductor region 212.

Referring to FIG. 65, cooling trenches 218 have been etched intoinsulative layer 204 to silicon-containing semiconductor region 212.Where material 206 is provided, cooling trenches 218 are also etchedtherethrough as shown in the depicted embodiment.

Referring to FIG. 66, a bridging material 220 has been selectively grown(relative to the insulative layer, at least) over insulative layer 204effective to bridge across cooling trenches 218 with bridging material,and form covered elongated cooling trenches 224. Example materials anddimensions for, and methods of forming, bridging material 220 are asdescribed above in other embodiments for the covering of voids/trenches.Of course as in embodiments described elsewhere in this document,epitaxial seed materials and seed materials such as disclosed may beutilized, and regardless growth of epitaxial material may occur frombases of openings 218, for example as shown. Regardless, coveredelongated cooling trenches 224 may, at this point or later, be partiallyfilled with one or more of insulative, semiconductive, and/or conductivematerials.

Referring to FIG. 67, and in but one example embodiment, an insulatorlayer 223 has been formed on an outer surface of bridging material 220bridging across cooling trenches 218. In one embodiment, such is formedto have a substantially planar outer surface 225.

Referring to FIG. 68, at interface 215 of release region 210 (not shown)and silicon-containing semiconductor region 212, separation has occurredof a) base region 208 (not shown) and release region 210 (not shown)from b) silicon-containing semiconductor region 212, insulative layer204 with covered elongated cooling trenches 224, and bridging material220. By way of example only, techniques for doing so include so-called“smart-cut techniques”, and for example as described in U.S. Pat. No.6,184,111.

Referring to FIG. 69 and in but one embodiment, substrate 200 has beenbonded with a carrier substrate 230. In one embodiment, carriersubstrate 230 comprises some base substrate 232 having an oxide layer234 formed thereover. Insulator layer 223 of substrate 200 has beenbonded to carrier substrate 230, and in the depicted embodiment to oxidelayer 234 thereof. Regardless, at least one of field effect transistorchannel regions or field effect transistor source/drain regions areformed within silicon-containing semiconductor region 212, and coolingfluid is provided within cooling trenches 224.

For example, FIG. 70 depicts subsequent processing wherein a gatedielectric 240 has been formed over silicon-containing semiconductorregion 212, and gates constructions 242 have been formed thereover. FIG.70 also depicts channel regions 250 and source/drain regions 252 beingformed in silicon-containing semiconductor region 212. Cooling fluid mayultimately be provided within the covered elongated cooling trenches.Such cooling fluid may comprise flowing gas, for example air, and/or asuitable flowing liquid.

The above example FIGS. 64-70 embodiment encompasses a method whereinthe release region was formed prior to the etching to form trenches 218.FIGS. 71-73 depict an alternate embodiment substrate portion 200 awherein the release region is formed after the etching to form thecooling trenches. Like numerals from the first-described embodiment areutilized where appropriate, with differences being indicated with thesuffix “a”. Referring to FIG. 71, base substrate 202 a comprises a baseregion 208 a and silicon-containing semiconductor region 212 a which isvoid of a defined release region, at least at this point in the process.

Referring to FIG. 72, cooling trenches 218 have been etched intoinsulative layer 204 to silicon-containing semiconductor region 212.

Referring to FIG. 73, release region 210 a has been formed intermediatesilicon-containing semiconductor region 212 a and base region 208 a.Such may be formed, by way of example only, by implanting one or more ofhydrogen atoms and/or oxygen atoms. A wholly or partially sacrificialplanarized layer may be provided over substrate 200 a prior to suchimplanting effective to fill openings 218 to provide uniform thicknessmaterial for ion implanting therethrough to form release region 210 a.Processing may proceed subsequently as described above, or otherwise,with respect to the FIGS. 64-70 embodiment.

Embodiments of methods of forming a semiconductor-on-insulator substrateare next described with reference to FIGS. 105 and 106 with respect to asubstrate portion 200 b. Like numerals from the FIGS. 64-70 substrateportion 200 embodiment are utilized where appropriate, with differencesbeing indicated with the suffix “b” or with different numerals.

Referring to FIG. 105, alternate processing to that depicted by FIG. 70is shown. Specifically, suitable gate dielectric material 227 andconductive first field effect transistor gates 229 have been formedwithin trenches 224. Accordingly in this embodiment at least withrespect to the depicted trenches 224, such do not function as coolingtrenches within which cooling fluid is ultimately received.

Referring to FIG. 106, gate dielectric 231 has been formed oversilicon-containing semiconductor region 212. Second field effecttransistor gates 233 have been formed opposite first field effecttransistor gates 229 over silicon-containing semiconductor region 212.Field effect transistor channel regions 235 have been formed withinmaterial of silicon-containing semiconductor region 212 received betweenfirst field effect transistor gates 229 and second field effecttransistor gates 233. Source/drain regions 237 have been formed withinsilicon-containing semiconductor region 212. Processing sequence toproduce the FIG. 106 structure may of course be in any order withrespect to components/regions 227, 229, 231, 233, 235, and 237.Processing may otherwise occur as described above with respect to eitherof the FIGS. 64-70 embodiment or the FIGS. 71-73 embodiment, and by wayof examples only.

Some embodiments herein include electromagnetic radiation guides (suchas conduits) and methods of forming electromagnetic radiation guides. Anexample embodiment is described with reference to FIGS. 74-79.

Referring to FIG. 74, a semiconductor construction 300 comprises a base302 and a material 304 over the base. The base 302 may comprise one ormore semiconductor materials, such as silicon or germanium. In someembodiments, the base may be configured to generate electromagneticradiation upon appropriate electrical stimulus. In such embodiments, thebase may comprise, consist essentially of, or consist of III/IV material(for example, may contain one or more of InAlP, GaS, and GaN), or aII/VI material (for example, may contain one or both of zinc selenideand cadmium telluride).

Material 304 is ultimately patterned into projections over base 302, andmay comprise any material suitable to form such projections. Material304 may be electrically insulative, conductive or semiconductive. Insome embodiments, material 304 is electrically insulative and comprises,consists essentially of, or consists of silicon dioxide and/or siliconnitride.

Referring to FIG. 75, material 304 is patterned into a plurality ofprojections 306, with such projections being spaced from one another bygaps 308 extending to base 302. Although the gaps are shown extendingonly to an upper surface of base 302, in other embodiments the gaps mayextend into base 302.

Material 304 may be patterned utilizing any suitable processing. Forinstance, photolithographically patterned photoresist may be providedover material 304 to define the pattern which is ultimately be formed inmaterial 304; an etch may be conducted to transfer the pattern from thephotoresist to the material 304; and subsequently the photoresist may beremoved to leave the construction of FIG. 75.

Referring to FIG. 76, a metal-containing layer 310 is formed alongsidewalls of projections 306 within openings 308. The metal-containinglayer may comprise, consist essentially of, or consist of one or more ofelemental metal (such as titanium or tungsten), metal alloys, andmetal-containing compositions (such as metal nitride). Themetal-containing layer 310 may be formed to line only the sidewalls ofprojections 304 by any suitable processing. For instance, themetal-containing material may be initially formed as a layer extendingacross an entire upper topography of construction 300, and then suchlayer may be subjected to an anisotropic etch to leave the constructionof FIG. 76.

Referring to FIG. 77, seed material 312 is formed over upper surfaces ofprojections 304. The seed material may be formed by a selectivedeposition onto the upper surfaces of projections 304, or may be formedby a non-selective deposition followed by an etch. Although the seedmaterial is formed after the patterning of projections 306 in the shownembodiment, in other embodiments the seed material may be provided overmaterial 304 prior to the patterning of the projections. In such otherembodiments, the seed material may be patterned during the patterning ofthe projections.

The seed material may comprise any of the seed materials discussedpreviously in this disclosure. Accordingly, the seed material maycomprise crystalline semiconductor material, tungsten, titanium,silicide, etc.

Referring to FIGS. 78 and 79, a covering material 314 is grown from theseed material to bridge across the projections 306. The material 314 maycomprise the same composition as the seed material 312. Accordingly,material 314 may merge with the seed material to form a singlehomogeneous composition extending across the projections 306 andbridging over the openings 308.

FIG. 79 shows that the openings 308 form a plurality of conduitsextending over base 302. In operation, base 302 may be stimulated togenerate electromagnetic radiation which enters the conduits and is thenguided by the conduits to desired locations. The electromagneticradiation may comprise any suitable wavelength, and in some embodimentsmay correspond to visible light. The metal-containing lining (orcladding) 310 may polarize electromagnetic radiation generated by base302. In some embodiments, the metal-containing lining may be omitted.

Openings 308 may be open spaces at the processing stage of FIG. 78 (asshown), or may be at least partially filled with material. For instance,a material may be provided within the openings that has refractiveproperties different from those of base 302, cover 314 andmetal-containing layer 310 to enhance retention of electromagneticradiation within the conduits. If the openings are to be at leastpartially filled with material, such material may be provided prior tothe formation of cover 314 across the openings in some embodiment.

In some embodiments, base 302 may comprise a composition which is not anelectromagnetic radiation emitter, and instead electromagnetic radiationmay be introduced into the conduits from a source other than the base.

Another example embodiment method of forming an electromagneticradiation guide is described with reference to FIGS. 80-84.

Referring to FIG. 80, a construction 320 comprises a base 322 having aplurality of projections 324 supported thereover. The projectionscomprise a material 326 and another material 328. In some embodiments,base 322 may comprise monocrystalline silicon, material 326 may comprisesilicon dioxide, and material 328 may comprise monocrystalline silicon.Accordingly, construction 320 may correspond to a patternedsilicon-on-insulator (SOI) structure similar to that of FIG. 61. In someembodiments, base 322 may be considered to comprise a first material,material 326 may be considered a second material, and material 328 maybe considered a third material. In some embodiments, material 328 maycomprise one or more of elemental-form tungsten, elemental-formtitanium, or silicide.

Referring to FIG. 81, covering material 330 is epitaxially grown frommaterial 328, and accordingly material 328 functions as a seed layer.Material 330 may comprise monocrystalline silicon, and accordingly maycomprise the same composition as the material of base 322.

The growth of material 330 forms conduits 332 contained betweenprojections 324, base 322, and a cover defined by material 330.

Referring to FIG. 82, materials 328 and 330 may be oxidized to form anoxide 334. In embodiments in which material 326 comprises silicondioxide, and materials 328 and 330 comprise silicon, such oxidation mayform oxide 334 to be a silicon dioxide which merges with the siliconoxide of projections 326, as shown.

Referring to FIGS. 83 and 84, conduits 332 are lined with material 340,and the lined conduits are then filled with material 342. The materials340 and 342 may be chosen to have light-refracting characteristics whichsubstantially retain particular wavelengths of electromagnetic radiationwithin the conduits so that such wavelengths may be guided by theconduits from one location to another. For instance, one or both ofmaterials 340 and 342 may have different light refracting propertiesthan the material of base 332, or one or both of materials 326 and 334.In some embodiments, materials 328 and 330 will not be oxidized to formmaterial 334, and in such embodiments one or both of materials 340 and342 may have different light refracting properties than one or both ofmaterials 328 and 330. In some embodiments, one or both of the materials340 and 342 may be omitted. In some embodiments, one or both ofmaterials 340 and 342 may comprise metal. The metal may be in elementalform, alloy form, or in the form of a metal-containing composition (forexample a nitride or a silicide).

FIG. 84 shows that conduits 332 having the materials 340 and 342 thereinform electromagnetic radiation-guiding paths. Specifically,electromagnetic radiation is diagrammatically illustrated by arrows 344as entering the conduits at one end, being directed along the conduits,and exiting the conduits at another end.

Some embodiments herein include imager systems and methods of formingimager systems. An example embodiment is described with reference toFIGS. 85-89.

Referring to FIG. 85, a construction 350 comprises a semiconductor base352 and a material 354 formed over the base. The material 354 maycomprise an electrically conductive composition, and may accordinglycomprise metal, metal-containing compounds, and/or conductively-dopedsemiconductor material. The material 354 comprises a differentcomposition than semiconductor base 352. In some embodiments, base 352may comprise monocrystalline silicon.

A seed region 356 is provided over material 354. An approximate boundarywhere the seed material joins material 354 is diagrammaticallyillustrated with a dashed line 355. In some embodiments, the seedmaterial may be identical in composition to the remainder of material354, and is defined only by its location at an uppermost region ofmaterial 354 from which growth of additional materials ultimatelyoccurs. The seed regions may comprise monocrystalline silicon. In someembodiments, both material 354 and material 356 comprise, consistessentially of, or consist of monocrystalline silicon. In otherembodiments, material 354 comprises a composition other thanmonocrystalline silicon, while material 356 comprises, consistsessentially of, or consists of monocrystalline silicon. In such otherembodiments, material 354 may comprise one or more electricallyconductive compositions, such as elemental metal and/or one or moremetal-containing compounds.

Referring to FIG. 86, material 354 and seed material 356 are patternedto form a plurality of openings 358 extending to base 352, and to form aplurality of projections 360 comprising material 354 and seed material356. Materials 354 and 356 may be patterned by any suitable method. Forinstance, a photolithographically patterned photoresist mask may beformed over the materials, a pattern may be transferred from the mask tothe materials with the one or more suitable etches, and then the maskmay be removed to leave the construction of FIG. 86.

Referring to FIG. 87, openings 358 are at least partially filled withdielectric material 362. In the shown embodiment, the openings areentirely filled with dielectric material 362 and a planarized surface363 extends across material 356 and dielectric material 362. Theconstruction of FIG. 87 may be formed by providing dielectric material362 to entirely fill the openings 358 and to extend across projections360, followed by planarization (for example chemical-mechanicalpolishing) to remove material 362 from over the projections and form theshown planarized surface 363. Dielectric material 362 may comprise,consist essentially of, or consist of silicon dioxide. In someembodiments, the openings may be left open rather than being at leastpartially filled with dielectric material (in other words, theprocessing of FIG. 87 may be omitted).

Referring to FIG. 88, monocrystalline silicon 364 is grown from seedmaterial 356, and over openings 358. In the shown embodiment, theopenings 358 are filled with dielectric material 362, and accordinglymonocrystalline silicon 364 is grown over such dielectric material.

Referring to FIG. 89, a pixel 370 (specifically, a CMOS imager device)is formed to be supported by monocrystalline silicon 364. The pixelincludes first and second gate constructions 371 and 373, andsource/drain regions 372, 382 and 384; with source/drain region 372corresponding to a photodiode. The photodiode extends across severalpockets of dielectric material 362. The buried dielectric material 362may provide some electrical isolation to charge flowed into theunderlying base 352, without excluding the ability to use conventionalisolation structures, (such as the shallow trench isolation structures374), to isolate pixels from one another in layer 364.

The pockets of dielectric material 362 may have sub-wavelength width anddepth dimensions relative to wavelengths of visible light. Suchsub-wavelength width and depth dimensions of the pockets may reduce lossof incident light and improve sensitivity of the pixel. Since siliconhas a different index of refraction than dielectric material 362, someincident light passing through layer 364 will be reflected at theinterfaces between dielectric material 362 and material 364. Lightreflected at the silicon-dielectric interface is redirected to thephotodiode of the pixel, as shown diagrammatically with arrows 375representing light in FIG. 89.

Pixel 370 may be one of numerous identical pixels of a pixel array.Pixel cross-talk between the various pixels of the array may be reduceddue to buried dielectric 362 reducing pixel-to-pixel carrier mobilitywithin base 352.

Some embodiments herein include fluorimetry systems and fluorimetrymethods. An example embodiment is described with reference to FIGS.90-93.

Referring to FIG. 90, a construction 400 comprises a base 402 having aplurality of projections 404 supported thereover. The projectionscomprise a material 406 and another material 408. In some embodiments,base 402 may comprise monocrystalline silicon, material 406 may comprisesilicon dioxide, and material 408 may comprise monocrystalline silicon.Accordingly, construction 400 may correspond to a patterned SOIstructure similar to that of FIG. 61. The material 408 may be referredto as a seed material.

The projections 404 are spaced from one another by gaps 405 that extendto base 402.

Referring to FIG. 91, monocrystalline semiconductor material 410 isgrown from seed material 408 to form a cover extending across gaps 405.

Referring to FIG. 92, materials 408 and 410 (FIG. 91) are oxidized toform an oxide material 412. In the shown embodiment, oxide 412 comprisesthe same material as 406 so that the oxide 412 merges with material 406.FIG. 92 also shows base 402 oxidized to form an oxide 414. The oxide 414is shown being of the same composition as material 406 so that the oxide414 and material 406 merge as a single material. In some embodiments,material 406 and oxides 412 and 414 all consist essentially of, orconsist of silicon dioxide.

The oxides 406, 412 and 414 surround gaps 405. In some embodiments, theoxides 406, 412 and 414 may be considered windows surrounding conduitscorresponding to gaps 405. Such windows are transparent to variouswavelengths of electromagnetic radiation, and accordingly theconstruction 400 of FIG. 92 may be utilized as a sample-retainingstructure of a fluorimeter. FIG. 93 shows a perspective view of theconstruction of FIG. 92 and shows a fluid sample 420 within one of theconduits corresponding to a gap 405. The view of FIG. 93 alsodiagrammatically illustrates the conduits beneath material 414 indashed-line view.

FIG. 93 shows an electromagnetic radiation emitting source 422, and anelectromagnetic radiation detector 424. The detector and emitter arearranged at right angles relative to one another as is typical offluorimeters. In operation, radiation 423 is directed toward sample 420from source 422, causing a component of the sample to fluoresce. Thefluorescence 425 is then detected by detector 424.

Although the emission is shown going through one of the projections anddetection shown through the cover 414, in other embodiments the relativelocations of the detector and emitter could be reversed. Also, in someembodiments one of the detector and emitter could be positioned beneathbase 414.

Some embodiments herein include nanofluidic channels and methods offorming nanofluidic channels. An example embodiment is described withreference to FIGS. 94-98.

Referring to FIGS. 94 and 95, a construction 500 comprises a base 502having a plurality of projections 504 supported thereover. Theprojections comprise a material 506 and another material 508. In someembodiments, base 502 may comprise monocrystalline silicon, material 506may comprise silicon dioxide, and material 508 may comprisemonocrystalline silicon. Accordingly, construction 500 may correspond toa patterned SOI structure similar to that of FIG. 61. The material 508may be referred to as a seed material.

The projections 504 are spaced from one another by gaps (or trenches)505 that extend to base 502.

Portions of base 502 are conductively-doped to form conductive regions510 at the bottoms of gaps 505, while leaving insulative regions 512adjacent the conductive regions. The top view of FIG. 95 shows that insome embodiments only portions of the base at the bottoms of the gaps505 are doped to form the regions 510. Accordingly, there are alsoinsulative regions 512 along some portions of the base at the bottoms ofthe gaps 505.

Referring to FIGS. 96 and 97, monocrystalline semiconductor material 514is grown from seed material 508 to form a cover extending across gaps505. Such converts the gaps into conduits extending between cover 514and base 502. Portions of cover 514 are conductively-doped to formconductive regions 520 over gaps 505, while leaving insulative regions522 adjacent the conductive regions. The top view of FIG. 97 shows thatin some embodiments only portions of the cover over the gaps 505 aredoped to form the regions 520, so that there are also insulative regions522 of the cover directly over some portions of the gaps 505. The gaps505 are diagrammatically illustrated in dashed-line view in FIG. 97 toassist the reader in understanding the location of the gaps relative tothe shown conductive and insulative regions of the cover 514.

FIG. 98 shows a perspective view of the construction of FIGS. 96 and 97,and shows fluidic samples 530 within the conduits corresponding to gaps505. The view of FIG. 98 also diagrammatically illustrates the conduits505 beneath material cover 514 in dashed-line view.

The conductive regions 510 and 520 form paired conductive plates offsetfrom one another by spaces corresponding to conduits 505. The pairedconductive plates are electrically connected to monitoring apparatuses550, 552 and 554. The monitoring apparatuses may monitor electricalproperties between the paired plates to detect changes occurring as asample fluid 530 passes between the plates. Such changes may becatalogued relative to various macromolecules (such as, for example,nucleotides or proteins) so that construction 500 of FIG. 98 mayultimately be utilized for characterization and/or sequencing ofmacromolecules. Although three separate monitoring apparatuses 550, 552and 554 are shown, in other embodiments the monitoring apparatuses maybe encompassed by a single processor.

The conductive plates may be considered to be a detection system whichmonitors at least one electrical property of fluid material passingbetween the plates.

There has been significant research directed toward utilization ofnanofluidic channels (in other words, channels having at least somedimensions on the order of nanometers) for sequencing and/or othercharacterization of macromolecules. It has proven difficult to fabricatenanofluidic channels using conventional processes. However, someprocessing as disclosed herein may be utilized to fabricate nanofluidicchannels as shown in FIGS. 94-98. Further, semiconductor processing maybe used to fabricate conductive plates on opposing sides of thechannels, and such conductive plates may then be utilized for monitoringmaterials flowed through the channels. The conductive plates may beconductively-doped regions of semiconductor material (as shown), and/ormay comprise patterned metal-containing materials.

Various of the structures described in this disclosure may beincorporated into electronic systems.

FIG. 99 illustrates an embodiment of an electronic system correspondingto a computer system 600. Computer system 600 includes a monitor 601 orother communication output device, a keyboard 602 or other communicationinput device, and a motherboard 604. Motherboard 604 may carry amicroprocessor 606 or other data processing unit, and at least onememory device 608. Memory device 608 may comprise an array of memorycells, and such array may be coupled with addressing circuitry foraccessing individual memory cells in the array. Further, the memory cellarray may be coupled to a read circuit for reading data from the memorycells. The addressing and read circuitry may be utilized for conveyinginformation between memory device 608 and processor 606. Such isillustrated in the block diagram of the motherboard 604 shown in FIG.100. In such block diagram, the addressing circuitry is illustrated as610 and the read circuitry is illustrated as 612.

Processor device 606 may correspond to a processor module, and maycomprise various of the structures described in this disclosure.

Memory device 608 may correspond to a memory module, and may comprisevarious of the structures described in this disclosure.

FIG. 101 illustrates a simplified block diagram of a high-levelorganization of an electronic system 700. System 700 may correspond to,for example, a computer system, a process control system, or any othersystem that employs a processor and associated memory. Electronic system700 has functional elements, including a processor 702, a control unit704, a memory device unit 706 and an input/output (I/O) device 708 (itis to be understood that the system may have a plurality of processors,control units, memory device units and/or I/O devices in variousembodiments). Generally, electronic system 700 will have a native set ofinstructions that specify operations to be performed on data by theprocessor 702 and other interactions between the processor 702, thememory device unit 706 and the I/O device 708. The control unit 704coordinates all operations of the processor 702, the memory device 706and the I/O device 708 by continuously cycling through a set ofoperations that cause instructions to be fetched from the memory device706 and executed. The memory device 706 may comprise various of thestructures described in this disclosure.

FIG. 102 is a simplified block diagram of an electronic system 800. Thesystem 800 includes a memory device 802 that has an array of memorycells 804, address decoder 806, row access circuitry 808, column accesscircuitry 810, read/write control circuitry 812 for controllingoperations, and input/output circuitry 814. The memory device 802further includes power circuitry 816, and sensors 820, such as currentsensors for determining whether a memory cell is in a low-thresholdconducting state or in a high-threshold non-conducting state. Theillustrated power circuitry 816 includes power supply circuitry 880,circuitry 882 for providing a reference voltage, circuitry 884 forproviding a first wordline with pulses, circuitry 886 for providing asecond wordline with pulses, and circuitry 888 for providing a bitlinewith pulses. The system 800 also includes a processor 822, or memorycontroller for memory accessing.

The memory device 802 receives control signals from the processor 822over wiring or metallization lines. The memory device 802 is used tostore data which is accessed via I/O lines. At least one of theprocessor 822 or memory device 802 may comprise various of thestructures described in this disclosure.

The various electronic systems may be fabricated in single-packageprocessing units, or even on a single semiconductor chip, in order toreduce the communication time between the processor and the memorydevice(s).

The electronic systems may be used in memory modules, device drivers,power modules, communication modems, processor modules, andapplication-specific modules, and may include multilayer, multichipmodules.

The electronic systems may be any of a broad range of systems, such asclocks, televisions, cell phones, personal computers, automobiles,industrial control systems, aircraft, etc.

In compliance with the statute, the subject matter disclosed herein hasbeen described in language more or less specific as to structural andmethodical features. It is to be understood, however, that the claimsare not limited to the specific features shown and described, since themeans herein disclosed comprise example embodiments. The claims are thusto be afforded full scope as literally worded, and to be appropriatelyinterpreted in accordance with the doctrine of equivalents.

1. A method of forming a transistor, comprising: providing exposeddifferent first and second materials on a semiconductor substrate, thesecond material comprising a pair of projections projecting upwardlyrelative to the first material and comprising sidewalls; providing anexposed third material atop the second material projections, the thirdmaterial being different from the second material; relative to thesecond material, selectively growing additional first material from theexposed first material and selectively from the exposed third materialeffective to bridge across the pair of second material projections toform a covered void between the pair of projections; and forming gatedielectric and conductive gate material within the covered void.
 2. Themethod of claim 1 comprising providing the third material to be the sameas the first material.
 3. The method of claim 1 comprising providing thethird material to be different from the first material.
 4. The method ofclaim 1 comprising providing the first material to comprisemonocrystalline elemental-form silicon, and the selectively growingcomprises epitaxial silicon-comprising growth from the first material.5. The method of claim 4 comprising providing the third material tocomprise elemental-form silicon.
 6. The method of claim 5 comprisingproviding the third material to comprise elemental-form amorphoussilicon.
 7. The method of claim 5 comprising providing the thirdmaterial to comprise elemental-form monocrystalline silicon, and whereinthe selectively growing comprises monocrystalline epitaxialsilicon-comprising growth from the elemental-form monocrystallinesilicon.
 8. The method of claim 7 comprising providing themonocrystalline elemental-form silicon first material to comprise a<100> plane direction, the exposed elemental-form monocrystallinesilicon third material comprising a <100> plane direction which isparallel that of the first material.
 9. The method of claim 5 whereinthe selectively growing comprises polysilicon-comprising growth from thethird material.
 10. The method of claim 4 comprising providing the thirdmaterial to comprise any one or more of elemental-form W, elemental-formTi, or a silicide.
 11. The method of claim 1 comprising providing thethird material to comprise elemental-form silicon, and the selectivelygrowing comprises growing any one or more of elemental-form W or asilicide.
 12. The method of claim 1 comprising providing the thirdmaterial to comprise elemental-form silicon and elemental-form Ge. 13.The method of claim 1 comprising providing the third material tocomprise Ga and As.
 14. The method of claim 1 comprising providing thesecond material to be insulative.
 15. The method of claim 14 comprisingproviding the second material to comprise at least one of silicondioxide or silicon nitride.
 16. The method of claim 1 comprisingproviding the second material to be conductive.
 17. The method of claim1 comprising providing the pair of projections to comprise walls of anopening.
 18. The method of claim 17 comprising providing the opening tocomprise an elongated trench running generally parallel a mean outermostglobal surface of the semiconductor substrate.
 19. The method of claim 1wherein the selectively growing is devoid of growing detectable firstmaterial from at least a majority of the second material sidewalls. 20.The method of claim 1 wherein the selectively growing comprises growinga semiconductive material, and further comprising providing field effecttransistor source/drain regions within the selectively grownsemiconductive material.
 21. The method of claim 1 wherein theselectively growing comprises growing a semiconductive material, andfurther comprising providing a field effect transistor channel regionwithin the selectively grown semiconductive material.
 22. The method ofclaim 1 wherein the selectively growing is at a selectivity relative tothe second material of at least ten to one.
 23. The method of claim 1wherein the selectively growing is at a selectivity relative to thesecond material of at least one hundred to one.
 24. The method of claim1 wherein the selectively growing of the first material is of least 100Angstroms and at a selectivity relative to the second material of atleast one hundred to one.
 25. A method of forming a transistor,comprising: forming a pair of projections projecting upwardly from asemiconductor substrate, the projections comprising sidewalls; providingelemental-form silicon atop the pair of projections; selectively growingrelative to at least portions of the projection sidewalls apolysilicon-comprising material from the elemental-form siliconeffective to bridge across the pair of projections to form a coveredvoid between the pair of projections; and forming gate dielectric andconductive gate material within the covered void.
 26. The method ofclaim 25 wherein providing the elemental-form silicon comprisesdepositing amorphous silicon, and annealing the amorphous silicon to bepolycrystalline; and wherein the selectively growing occurs from thepolycrystalline silicon.
 27. A method of forming a plurality oftransistors, comprising: depositing insulative material over anelemental-form silicon-containing material; depositing amorphous siliconover the insulative material; etching a plurality of openings throughthe amorphous silicon and the insulative material to the elemental-formsilicon-containing material; selectively growing relative to theinsulative material an elemental-form silicon-comprising material fromthe elemental-form silicon-containing material and from the amorphoussilicon effective to bridge across the plurality of openings to coverthe plurality of openings; and forming gate dielectric and conductivegate material within the covered plurality of openings.
 28. The methodof claim 27 wherein the etching forms the plurality of openings tocomprise elongated trenches running generally parallel a mean outermostglobal surface of the semiconductor substrate.
 29. The method of claim27 wherein the etching forms the plurality of openings to compriseelongated trenches running generally parallel a mean outermost globalsurface of the semiconductor substrate; providing individual of thecovered elongated trenches to have at least one open end; and depositingthe conductive gate material to within the covered elongated trenchesfrom the at least one open end.
 30. A method of forming a plurality oftransistors, comprising: depositing insulative material over a firstelemental-form silicon-containing material; forming a secondelemental-form silicon-containing material over the insulative material;etching a plurality of openings through the second elemental-formsilicon-containing material and the insulative material to the firstelemental-form silicon-containing material; epitaxially growing a firstelemental-form silicon-comprising material from the first elemental-formsilicon-containing material; selectively growing relative to theinsulative material a second elemental-form silicon-comprising materialfrom the second elemental-form silicon-containing material effective tobridge across the plurality of openings to cover the plurality ofopenings; and forming gate dielectric and conductive gate materialwithin the covered plurality of openings.
 31. The method of claim 30wherein the forming of the second elemental-form silicon-containingmaterial comprises depositing amorphous silicon.
 32. The method of claim31 comprising annealing the amorphous silicon to be polycrystalline, andwherein the selectively growing forms the second elemental-formsilicon-containing material to be polycrystalline.
 33. The method ofclaim 30 wherein the forming of the second elemental-formsilicon-containing material comprises forming monocrystalline silicon.34. The method of claim 33 wherein the selectively growing comprisesepitaxially growing the second elemental-form silicon-comprisingmaterial.
 35. A method of forming a plurality of transistors,comprising: depositing insulative material over an elemental-formsilicon-containing material; forming an amorphous elemental-formsilicon-containing material over the insulative material; etching aplurality of openings through the amorphous elemental-formsilicon-containing material and the insulative material to theelemental-form silicon-containing material; annealing the amorphouselemental-form silicon-containing material effective to form apolycrystalline silicon-containing material; epitaxially growing a firstelemental-form silicon-comprising material from the elemental-formsilicon-containing material while selectively growing relative to theinsulative material a polysilicon-comprising material from thepolycrystalline silicon-containing material effective to bridge acrossthe plurality of openings to cover the plurality of openings; andforming gate dielectric and conductive gate material within the coveredplurality of openings.
 36. A method of forming field effect transistors,comprising: providing a monocrystalline silicon-containing substratecomprising a <100> plane direction; depositing insulative material overthe monocrystalline silicon-containing substrate; etching a plurality oftrenches through the insulative material to silicon-containing materialof the substrate parallel the <100> plane direction and providingmonocrystalline silicon-containing material bases of the trenches whichrun parallel the <100> plane direction; epitaxially growing anelemental-form silicon-comprising material from the monocrystallinesilicon-containing material of the trench bases and over the insulativematerial effective to bridge across the trenches with elemental-formsilicon-comprising material and form covered trench voids within thetrenches; and forming at least one of field effect transistor channelregions or field effect transistor source/drain regions within theelemental-form silicon-comprising material bridging across the trenches.